Skip to main content
LakeQuality

Sleepy Eye Lake Water Temperature

Sleepy Eye Lake in Brown County, Minnesota averages about 79°F at the surface in summer — warmest in Jul (~81°F) and coldest in Oct (~52°F). These are typical values by month, not a live reading.

Typical in July
81°F
Warm
Summer average
79°F
Warmest (Jul)
81°F
Coldest (Oct)
52°F

Typical water temperature by month

Jan
Feb
Mar
Apr
May
65°
Jun
79°
Jul
81°
Aug
76°
Sep
69°
Oct
52°
Nov
Dec

Typical surface water temperature by month, from 96 field readings (20172023) via the EPA Water Quality Portal. Months with too few readings are left blank.

Is Sleepy Eye Lake warm enough to swim?

At its summer peak (~79°F): Comfortable

Pleasant for swimming — the range most people find enjoyable without a wetsuit.

Want more than temperature? Sleepy Eye Lake scored D on water quality — clarity, algae, phosphorus, depth, fish species, and swimming safety, all on one report card.

Where to stay near Sleepy Eye Lake

Planning a swim or lake trip? Compare cabins, lodges, and vacation rentals near Sleepy Eye Lake — live availability and prices.

Top-rated places to stay near Sleepy Eye Lake

Availability and prices from Stay22 partners (Booking.com, Vrbo, Expedia). We may earn a commission from bookings, at no extra cost to you.

Planning a trip to Sleepy Eye Lake?

Get lake water-quality report cards plus the best cabin & lodging deals near Sleepy Eye Lake — straight to your inbox. No spam, unsubscribe anytime.

Frequently asked questions

What is the water temperature of Sleepy Eye Lake?

Sleepy Eye Lake has a typical summer surface temperature of about 79°F. It is usually warmest in July (around 81°F) and coldest in October (around 52°F). These are typical values by month from 96 EPA Water Quality Portal field readings (2017–2023), not a live reading.

When is Sleepy Eye Lake warmest?

Surface water at Sleepy Eye Lake is typically warmest in July, reaching about 81°F. Lake surface temperature lags air temperature by several weeks, so the warmest water usually arrives in mid-to-late summer even though the hottest air can come earlier.

Is Sleepy Eye Lake warm enough to swim?

At its typical summer peak of about 79°F, Sleepy Eye Lake rates as "comfortable" for swimming. Pleasant for swimming — the range most people find enjoyable without a wetsuit.

Where does this Sleepy Eye Lake water temperature data come from?

Every temperature on this page is a typical (climatological) value computed from real surface-water field readings collected by state and federal agencies and published through the EPA Water Quality Portal — 96 readings from 1 monitoring station between 2017 and 2023. They describe what is typical for each month, not the temperature right now.

About this data

Water temperatures are a climatology — the typical value for each month, averaged from real surface-water field readings collected by state and federal agencies and published through the EPA Water Quality Portal. They tell you what to expect, not the temperature at this moment. Actual conditions vary with recent weather, depth, and time of day.